Linear motion rolling contact guide unit having a damper-inserted transverse adjustable mechanism

Abstract

A linear motion rolling contact guide unit includes a rail, a slider assembly and a plurality of rolling members interposed between the rail and the slider assembly. The slider assembly includes a pair of lower and upper sub-assemblies. The lower sub-assembly is slidably mounted on the rail and the upper sub-assembly is mounted on the lower sub-assembly such that it may move transversely relative to the lower sub-assembly over a limited distance. A low friction intermediate member is provided at a first location in a gap between the opposed surfaces of the upper and lower sub-assemblies so as to provide an enhanced sliding characteristic therebetween. A squeeze film damper mechanism is provided at a second location in the gap between the upper and lower sub-assemblies for damping and/or absorbing undesired motion.

What is claimed is: 
     
       1. A linear motion rolling contact guide unit, comprising: a rail extending over a length;   a slider assembly slidably mounted on said rail, said slider assembly including a first sub-assembly, a second sub-assembly mounted on said first sub-assembly movably relative to said first sub-assembly in a predetermined direction, a low friction intermediate means interposed at a first location between said first and second sub-assemblies, and a squeeze film damper mechanism interposed at a second location, different from said first location, between said first and second sub-assemblies; and   a plurality of rolling members interposed between said rail and said first sub-assembly such that said slider assembly may move along said rail.   
     
     
       2. The unit of claim 1, wherein said predetermined direction is a transverse direction with respect to the longitudinal axis of said rail. 
     
     
       3. The unit of claim 2, wherein said rail is formed with a pair of guide grooves at its opposite side surfaces and said first sub-assembly is formed with a pair of endless circulating paths in which said plurality of rolling members are provided, each of said endless circulating paths including a load path section, a return path section and a pair of curved connecting path sections each connecting the corresponding ends of said load and return path sections, whereby said load path section is provided with an elongated window through which those rolling members located in said load path section are partly exposed to be received in the corresponding guide groove of said rail. 
     
     
       4. The unit of claim 2, wherein said low friction intermediate means includes a plurality of rollers interposed between said first and second sub-assemblies. 
     
     
       5. The unit of claim 2, wherein said low friction intermediate means includes a lubricating sheet of a low friction material. 
     
     
       6. The unit of claim 2, further comprising limiting means for limiting a relative movement between said first and second sub-assemblies in said predetermined direction to a predetermined amount. 
     
     
       7. The unit of claim 6, wherein said limiting means also serve to prevent the first sub-assembly from slipping away from said first sub-assembly. 
     
     
       8. The unit of claim 6, further comprising means for preventing said first sub-assembly from slipping away from sid first sub-assembly. 
     
     
       9. The unit of claim 1, wherein said squeeze film damper mechanism includes a gap defined at said second location between a pair of opposed surfaces of said first and second sub-assemblies and a quantity of fluid having a predetermined viscosity. 
     
     
       10. The unit of claim 9, wherein said fluid is oil. 
     
     
       11. The unit of claim 1, wherein said slider assembly is provided with a flow passage extending from an inlet opening formed in a surface of said slider assembly to said second location.